This invention relates generally to electrical apparatus, and more particularly, to a compressed gas-insulated transmission line made from a modular construction.
Compressed gas-insulated power transmission lines are a relatively recent commerical product which is gaining increased acceptance by the electric utility industry as an economical means for transmitting large blocks of electrical energy, and for use in special applications where conventional power transmission lines are inadequate. A typical compressed gas-insulated transmission line is comprised of an elongated outer sheath having disposed therein an inner conductor at high potential, with means disposed in the outer sheath to insulatably support the inner conductor within the outer sheath. An insulating gas, typical of which is sulfur hexafluoride at a pressure of 50 psi gauge, is utilized for electrically insulating the inner conductor from the outer sheath. Particle traps may be utilized to trap and deactivate contamination particles which may be present within the outer sheath. The inner conductor is typically used to transmit energy at voltage ranges from 121-1200 kV. Both the inner conductor and the outer sheath are of good electrically conducting materials such as aluminum.
One of the drawbacks of gas-insulated power transmission lines which is hindering even more widespread application of the lines is associated with the cost of the lines. If the cost of manufacturing and installing the gas-insulated transmission lines were further reduced, these lines would be more competitive with conventional power transmission lines for more and more installations.